The present invention relates generally to patient supports, such as those used in health care facilities, and more specifically to a pivoting assembly for a head portion of the patient support.
It is known in the prior art to provide a patient support, such as a hospital bed or stretcher, that includes a pivotable section for supporting the back and head of a patient. For example, U.S. Pat. No. 5,423,097 issued to Brule, discloses a hospital bed having a moveable upper body support. This upper body support is pivotable between a generally horizontal orientation in which the patient will be lying flat and a raised orientation in which the patient's upper body will be raised from the flat position. In many prior art beds, the pivoting of the upper body section—which is commonly referred to as the Fowler section of the bed—to and from the horizontal orientation creates shear forces between the patient and the hospital bed.
More specifically, as the Fowler section is rotated upwardly from the horizontal orientation, the patient's back and/or buttocks may be forced by the movement of the Fowler section to slide along the Fowler section and/or the seat section of the bed, respectively. This sliding motion is due to shear forces. In general, these shear forces are created because the patient's hip joint, which defines the axis of rotation for the patient's upper body, does not coincide with the axis of rotation about which the upper body section of the bed pivots. While attempts have been made in the past to mitigate these shear forces, such as by the reduced shear pivot disclosed in U.S. Pat. No. 7,017,208 issued to Weismiller, none of the prior art reduced shear pivots have offered a solution as simple, effective, and advantageous as that of the present invention.